1. Field of the Invention
The present invention relates generally to an articulation joint for connecting two sections of a vehicle, and in particular to such a joint for use in a vehicle which must be able to negotiate short radius turns. The joint may also be used in conveyors.
An important use of such an articulation joint is as a vertical pivot joint in an articulated shuttlecar for use in mining operations having a plurality of pivotally connected sections.
2. Description of the Prior Art
Articulation joints for use in conveyors, shuttlecars and other haulage vehicles are known in the art. Most equipment of this type includes horizontal pivot joints which permit the equipment to operate on undulating surfaces. In haulage vehicles with vertical pivot joints, the loading on the joints is generally low since the joint is normally between the cab portion of the vehicle and the load carrying portion of the vehicle.
U.S. Pat. No. 4,160,619 discloses a vertical pivot joint which is located in the middle of a mine shuttlecar. The pivot joint in that patent has spaced upper and lower plates on one part of the shuttlecar which are pivotally connected to spaced upper and lower plates on the other part of the shuttlecar. The pivotal connection incorporates bearing races, which are spaced apart to accommodate a pair of steering rams between them. Because of the spacing, the joint cannot withstand high loads. Also, the arrangement of the plates in the joint disclosed in that patent requires that the joint be assembled from above and from below, which is a disadvantage.